The "fat" comment proved a subtle nod to Mia's TikTok (see above), where she lip synced to audio from a Today show interview with teenage surfer Sabre Norris.
In the audio, longtime host Karl Stefanovic asked the surfer: "Is he an athlete, your dad?"
Mia then lip synced to Sabre's response in front of a photo of her dad on a football field: "Yeah my dad was an athlete but now he's, um, pretty fat," Mia mimed to the audio.
The post received a lot of love and affection, including from current I'm A Celeb star and dad himself Beau Ryan.
However, the couple rekindled in 2016 and soon announced they were engaged.
"I was a bit nervous, I didn't think she'd say yes," Brendan said of re-proposing to Alex on the then Fifi and Dave show.
"Because we've been married before and obviously been divorced. It was really beautiful with the kids there."
The couple are also proud parents to Leni, 15, Lulu, 12, and baby Tobi, three.
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